On the 25.00 contour plots a water type A where the isopycnal (density contour) crosses the 33% salinity line, and water type B where the isopycnal crosses the 3oC temperature line. Plot a point in the middle of this mixing line. Note that if it falls below and to the right of the 25.00 Qt contour and is therefore denser. This midpoint is the temperature and salinity of a 50-50 mixture of water types A and B. The line itself represents all possible mixtures of water types A and B and thus the water mass that would form from such a theoretical mixture.
What is the range of T and S that defines water mass produced by mixing water types A and B in all proportions? What is the density of the 50-50 mixture of water types A and B? What is the temperature of the 50-50 of water types A and B?
What is the salinity of the 50-50 mixture of water types A and B?